Much of the rising interest in wikis stems in part from the success of Wikipedia, a free online encyclopedia that relies on contributors to add and edit entries. Since its establishment in 2001, the English-language version has grown to include more than 480,000 entries and has generated versions in a host of other languages.

Wikipedia may be the best-known wiki, but it wasn't the first. The world's first wiki, a computer programming site called the Portland Pattern Repository, was established by Ward Cunningham in 1995.

How is a wiki different from a blog?

A wiki possesses an "edit this page" link that allows a visitor to make changes to the page. This link is what makes wikis different from Web logs, or blogs, which permit readers to give feedback on a particular comment but prevent them from editing anything but their own postings.

Blogs can be used to build communities of mutual interest. Wikis go a step beyond community and enable consensus-building. Imagine a team of people sitting around a whiteboard, where anyone can add to an idea, edit or erase it, and you've got a rough idea of what a wiki is.

What are the benefits of a wiki?

Given the hectic pace of doing business these days, bridging the distances between people and fostering idea-sharing can be a competitive advantage. Wikis also require only an Internet connection and a Web browser for access, which can make them easier to deploy and use than some collaborative applications or groupware offerings. Having people share information on the wiki can also ease overloaded in-boxes and cut down on e-mail exchanges between co-workers.

Why should marketers care about wikis?

Wikis have generated buzz because of Wikipedia's success, but the medium's corporate potential is just being explored. Wikis clearly can be used by companies for internal and external applications. For companies that have trouble keeping up-to-date information on a corporate intranet, wikis can enable employees and customers to make changes themselves. They can also help coordinate internal development projects -- an area in which they have already started to make corporate inroads.

Wikis can also be used to build online customer communities that offer advice and support. Some companies may balk at the idea of opening up a site such as this to the public, but the trust extended will likely be repaid with increased customer loyalty and satisfaction.

Who controls the content of a wiki?

In theory, no one and everyone. Every reader has control over a wiki's content and can make changes, additions or deletions as they see fit. This lack of centralized control can require a leap of faith for some organizations. Wikis may seem to be an invitation for anarchy -- an opportunity for online vandals to change or delete valuable content -- but in practice, this rarely occurs. Nevertheless, setting a few basic rules for how the wiki should be used won't hurt.

To prevent important information from being altered or deleted, systems administrators can "protect" certain wiki pages by disabling the ability to edit them. However, even if an important page is deleted or changed, don't worry. Wikis are online databases of information, and each modification is stored in the database so that information can be restored.

How do I get started?

There are several open-source software packages available for free downloading, including TWiki. Wikis are also available as hosted applications, such as Socialtext and JotSpot, which is still in beta.